The present invention relates generally to a linear motor, and more particularly to a self-lubricating mechanism of slide member.
FIG. 1 shows a conventional linear motor 1 having a mover 2 and a stator 3. The mover 2 is linearly reciprocally movable by means of the magnetic field effect between the mover 2 and the stator 3. The mover 2 is guided with linear guide rails 4 for controlling the linear track of the mover 2 and stabilizing the motion of the mover 2. The mover 2 is carried by sliders 5 slidably mounted on the slide rails 4, whereby the guide rails 4 can guide the mover 2 to reciprocally move.
To speak more specifically, ball bodies or rollers are held between the sliders 5 and the slide rails 4 to reduce frictional force so as to stabilize and smoothen the relative sliding motion of the sliders 5 along the slide rails 4. However, considerably great frictional force still exists between the ball bodies and the faces in contact with the ball bodies. Therefore, it is still necessary to lubricate the guide members.
FIG. 2 shows a conventional self-lubricating mechanism for lubricating the guide members. An oil reservoir 6 is connected with one side of the slider 5 for containing lubricating oil. The oil reservoir 6 has woolen felts 7 to provide capillary effect for feeding the lubricating oil reserved in the oil reservoir 6 between the ball bodies and the faces in contact therewith. In normal use environment, such mechanism is able to achieve a certain lubricating effect. However, in a vacuum operation environment, the lubricating oil will have very high viscosity so that the capillary effect will be unapparent. Therefore, the guide members can be hardly lubricated with such self-lubricating mechanism in the vacuum operation environment. However, most of the production equipments for the current high-precision semiconductor products or plane displays require vacuum environment.
FIG. 3 shows a conventional pump-pressurized lubricating mechanism. By means of an external pressurizing pump 8, the lubricating oil is pumped into the slider 5 through an oil tube 9. The lubricating oil is then filled between the ball bodies and the faces in contact therewith. When using a linear motor in a vacuum operation environment, such mechanism is able to achieve the purpose of lubrication. However, in the vacuum environment, there is no medium so that the heat generated by the pressurizing pump 8 cannot be dissipated via air. Moreover, the pressurizing pump 8 is an additional component with respect to the linear motor, which will occupy much room and lead to increment of load. Accordingly, the pump-pressurized lubricating mechanism is not an optimal lubricating measure for the linear motor.